All cellular activities that require energy use ATP as a source of energy.
If the food is limited to the squirrels then that could impact how well they reproduce which could impact their numbers which therefore could impact the food source for the foxes which eat them. Fewer squirrels means the foxes will slow down on their reproductive numbers as well...they are all linked!
Answer: To know if a document is a primary source, check to see when the document is published, if it is an autobiography of a person, a diary, a letter, or the documents happen at the time of the event.
The competition between two organisms can be seen if there is only 1 source of food or habitat space and they're competing against each other for the food or habitat.
There is cooperation between two organisms if they are helping each other with resources or alarming each other if there is danger.
Predation between two organisms happen when one organism hunts the other organism for food.
The major function of the contractile vacuole of amoeba is osmoregulation. The solute concentration found in the cell of amoeba's cytoplasm is more than the solute concentration in the freshwater that surround the external part of the organism, thus, water enter the cell through osmosis. The contractile vacuole collect the excess water and expel it through an opening in the cell membrane. By doing this, the contractile vacuole maintains the water balance in amoeba. This how the contractile vacuole normally operate.
In a situation where amoeba is placed in seawater, then water from the cell cytoplasm will rush out of amoeba cell, because of the higher salt content of the surrounding medium. The contractile vacuole will respond to the situation by increasing its contraction and pumping water out the cell in an accelerated manner, this will lead to the shrinking of the cell.